Planar Moving Flap Valve Structure for Microfluidic Control

This work describes the development of a planar moving flexible valve in polydimethylsiloxane (PDMS) with integrated optics components on a microfluidic device. Applying a positive pressure to a side channel, the fluid inside deforms the flexible PDMS which then redirects the flow in a main stream to an alternate output channel. Simulations of the fluid and solid interaction in two channel configurations are performed in COMSOLRTM using the Arbitrary Lagrangian-Eulerian (ALE) technique. As a result, the 5 microm and 10 microm flaps were able to be deformed and redirected by a moderate flow velocity. A silicon master was produced for making PDMS chips using standard replication molding technique. Using a commercial miniature peristaltic pump, a 10 microm flap is deflected in the microfabricated biochip by the fluid flowing from the side at an average flow rate of 130 microL/min in a 60 microm x 65microm channel.